1. From the Department of Neurology (D.C.L., M.I.R.-M., M.S., M.D.S., K.C.F., C.A.P., D.S.R., M.A., P.B.), Johns Hopkins University School of Medicine, Baltimore, MD; Translational Neuropathology Unit (E.P., M.A.), Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy and Translational Neuroradiology Section (D.S.R., M.A.), National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD.